Do you know someone who has walking pneumonia?

What is it? Why doesn't it cause fever? I know two elderly people who have been suffering this since early this year and they were were both obediently vaccinated.. Shortness of breath, and incapable of eliminating it completely. Both have been proscribed mucinex with no resolution. I had walking pneumonia for a few weeks but did not realize. I'm ok now I think. I'm unvaxxxxxxxxed.